The present invention relates generally to auto-transformers, and more specifically to an auto-transformer for use in power supplies.
As is well known, an auto-transformer is formed of a coil provided with first and second terminals connected to opposite ends of the coil and a third terminal connected to a tap between the ends of the coil. AC voltage from a mains voltage source is applied across the first and second terminals and a load circuit is connected across the third terminal and one of the first and second terminals. If several circuits of relatively small amount of load are connected in parallel to the auto-transformer, the total load current is a sum of individual load currents and hence the wire gauge of the auto-transformer increases with the total load current, resulting in a costly and bulky auto-transformer.